Injection Molding Apparatus and Method of Use

ABSTRACT

The present invention surrounds an apparatus and method for the use in injection molding of articles of manufacture using an injection molding apparatus having a valve-gate pin or a plurality of valve-gate pins for actuation to extend and retract from a cavity within an injection mold. The valve-gate pin may have a retention feature or retention features configured for the retention of molded parts such that the retraction or extension of the valve-gate pin provides part removal from an associated injection mold. Further, the valve-gate pin may have a feature or features to facilitate the injection of fluids, gases or particles during or after the primary injection process. Additionally, a plurality of such valve-gate pins may be employed within each mold cavity, or within each valve-gate actuation system.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit to provisional patent application No.62/326,655, entitled “Injection Molding Apparatus and Method of Use”,filed Apr. 22, 2016, which is incorporated by reference in its entiretyfor all purposes.

FIELD OF THE INVENTION

The present invention relates to an apparatus and process to decreasemaintenance and increase process efficiency surrounding injectionmolding.

BACKGROUND OF THE INVENTION

The field of injection molding surrounds a manufacturing process forproducing parts by injecting material into a mold having at least twoadjoining portions creating a specifically designed cavity resemblingthe form of the desired part to be made. After a part is designed, amold is manufactured from any suitable material, usually metals, andmachined to form the features of the desired part. This mold is usuallyaffixed to an injection molding machine which uses the mold to producethe part as designed. The injection molding process typically fills thecavity with a liquefied material which is then cooled, cured, andsolidified to produce the part as designed.

An injection mold typically has two or more parts. A first side,sometimes referred to as the A-side, is the side from which the materialis typically injected through an injector or valve-pin and into thecavity of the mold. The second side, sometimes referred to as theB-side, typically retains the part when the mold is open after thematerial injection process.

A typical injection molding process involves a series of steps. A firststep of clamping, secures the first side to the second side in a mannerthat aligns the cavity of the A-side with the cavity of the B-side inpreparation for the following steps. Following the clamping step, aninjecting step involves the preparation and delivery of material underpressure into the cavity of the mold. When the material is deliveredinto the cavity, the material for injection is initially fed into aheating chamber prior to being forced into the cavity. Material isdelivered into the cavity through a flow control system, often through avalve-gate system, such as disclosed by U.S. Pat. No. 5,948,450 toSwenson et al., the entirety of which is herein incorporated byreference. Such valve-gate systems are configured with a valve-pin thatopens/closes flush with the outer boundary of the mold cavity to preventinterference with part molding. As the material is injected into thecavity of the mold, a vent is commonly used to allow the equalization ofgasses to be purged from the cavity. Following the injecting step, adwelling step involves a pause in the injection process. During thedwelling step, maintaining the material motionless under pressure,ensures that all voids of the cavity are filled with the injectedmaterial. A cooling step then allows the material to cool and harden tothe configuration of the mold cavity. The mold is then opened and thepart removed. In many scenarios, an additional step of removing the partfrom the opened mold is required. Part removal is often performed by amachine attendant or using a mechanism referred to as an ejector pin orknock-out pin.

Ejector pins, as used in the injection molding industry, provide thefunctionality of ejecting or removing molded parts from a mold withoutthe direct physical involvement of a machine operator or attendant.Ejector pins have linear or rotational actuation functionality and aretypically installed in the second side, or B-side, of the mold. When themold is opened during the opening step, the ejector pins are actuated toextend the ejector pins outward from behind the molded part. Theactuation of the ejector pins pushes the part away from the mold whichreleases the part and allows it to fall away from the mold.

SUMMARY OF THE INVENTION

In the field of injection molding, a large portion of the related moldmaintenance is directly associated with the maintenance of ejector pins.Some injection molding manufacturers attribute 30-40% of the cost ofmold maintenance to the maintenance of ejector-pins and ejector-pinsystems. When a mold undergoes maintenance, this typically includesdown-time for the injection molding machine to which the mold isaffixed. Ejector pin systems are often the cause of excess wear and tearfor molds and as a result, molds are commonly made from steel, resultingin a heavy mold requiring costly machining to prepare.

Existing technologies surrounding the removal or ejection of a part froman injection mold include U.S. Pat. No. 6,872,069 to Starkey, U.S. Pat.No. 4,412,806 to Gaiser and Niepoky, U.S. Pat. No. 3,893,644 to Drazick,and U.S. Pat. No. 5,492,658 to Ohno et al., all of which are hereinincorporated by reference in their entirety.

The elimination of ejector pins decreases the need for mold maintenanceand decreases injection molding machine downtime. The elimination ofejector-pins also serves to allow the manufacture of injection moldsfrom alternative materials from traditionally used steel, and eliminatesinjection mold complexity amongst other advantages.

Certain embodiments of the invention provide functionality for themechanical extraction of a molded part from an injection mold whileeliminating the need for ejector pins. The elimination of ejector pinsserves to reduce mold preparation cost and decreases mold maintenancefrequency.

The invention as presented eliminates the necessity of an ejector pin byusing a valve-gate pin for part extraction. In certain embodiments, avalve-gate pin is installed on a first side of the mold with a distalportion of the valve-gate pin protruding into the cavity of the moldcavity. The valve-gate pin provides both the functionality ofcontrolling flow of the liquefied material into the cavity of the moldas well as extracting the part from the mold. When the part is molded,the part forms and solidifies around the protruding portion of thevalve-gate pin, thereby affixing the part to the protruding portion ofthe valve-gate pin. When the mold is opened, the part is pulled awayfrom the second side of the mold by the connection of the part to thevalve-gate pin, thus essentially retaining the part in the first side ofthe mold. Once the connection between the part and the valve-gate pin isbroken, the part may be removed. The valve-gate pin may be furtheractuated to retract or extend, to provide self-release of the part fromthe valve-gate pin.

The apparatus and method of use surrounding the invention may be usedfor pre-existing injection molding tools that use valve-gate pins tocontrol the flow of liquid material into the mold cavity. Valve-gatepins of existing molds may be replaced with multi-functional valve-gatepins for the delivery of molding material and to extract the molded partfrom a mold, eliminating the need for ejection pins.

The present invention surrounds an apparatus and method for theimprovement of the field of injection molding through the elimination ofejection pins by using valve-gate pins. Valve-gate pins as discussedherein provide the functionality of controlling the injection ofmaterial into a cavity of a mold through an aperture as well asextracting the part from the mold.

Certain embodiments of the invention allow the capability to preciselyand repeatedly control the position, speed and flow aperturecharacteristics of a valve-gate pin. The precise control of the positionof a valve-gate pin surrounding extension and retraction allows thefinite control and adjustability of the location of the valve-gate pinthroughout the injection molding process. The adjustment of flowaperture characteristics of the valve-gate pin allows for optimizationof flow characteristics for the parts being made after the injectionmold has been manufactured. In such embodiments, the valve-gate pin maybe used to influence the speed and flow characteristics of the materialentering the mold cavity, affecting part formation and effectiveness ofthe valve-gate pin to develop a desired connection to the molded part.

Certain embodiments of a valve-gate pin as described in the presentapplication further comprise pathway through the length or partiallength of the valve-gate pin, typically consistent with a central axisof the valve-gate pin. In such embodiments, the pathway provides theability to inject or push a fluid, or other material, into the cavitywithin the injection mold. Such practice of injecting a gaseous fluid inthe cavity of the injection mold with molten fluid, such as a polymer,is known as gas-assist injection molding such as disclosed by U.S. Pat.No. 6,019,918 to Guergov, the entirety of which is herein incorporatedby reference. Such a pathway may also be used for gas ejection of a partsuch as disclosed in U.S. Pat. No. 4,653,997 to Sheffield et al., theentirety of which is herein incorporated by reference.

In certain embodiments, a part may still be retained by a first side ofan injection mold after the retraction of a valve-gate pin. In suchembodiments, it may be further desired to extend the valve-gate pin suchthat it once again protrudes into the injection mold cavity. Theextension of the valve-gate pin following retraction serves to push thepart away from the first side of the mold and release the part from themold. The extension of the valve-gate pin following retraction may alsoserve to re-seal the part if additional fluids are injected through thevalve-gate pin.

Certain embodiments of the protruding portion of the valve-gate pincomprise a retention feature. Certain embodiments of a valve-gate pincomprise a retention feature having an undercut around the perimeter ofthe protruding portion of the valve-gate pin. An undercut in thissituation provides increased connection strength between the part andthe valve-gate pin following part molding. The retention feature of avalve-gate pin may comprise any form, dimension, depth or profile. Incertain embodiments, it may be desired to have a plurality of undercutsin the protruding portion of the valve-gate pin. A retention feature asdisclosed herein may comprise any form or feature known to those skilledin the art to provide an increased connection strength between a partand a valve-gate pin, including but not limited to, annular undercutfeatures, helical undercut features, threaded features. Certainembodiments of a valve-gate pin comprise retention features that exceeda diameter of a portion of the valve-gate pin which protrudes into thecavity of an injection mold.

The configuration of a retention feature of a valve-gate pin dependsupon the part for molding as well as the material used in the injectionmolding of the part. For instance, in the injection molding ofthermoplastic plastics, it is possible to obtain a molded product withthe desired dimensions using the mold shrinkage phenomenon. Moldshrinkage is the phenomenon where the volume of the flowable materialfilled inside the cavity of a mold shrinks at the same time as beingcooled and solidifying. The extent of this shrinkage is commonlyreferred to as a molding shrinkage factor. The value of the moldingshrinkage factor is generally a number in the range of about 0.02% to2%. It will be appreciated by those skilled in the art that the moldingshrinkage associated with a given injection mold and part is affected bytype of molding material, internal surface temperature of the injectionmold. In embodiments, such that a retention feature comprises anundercut, it may be desired to size the undercut in accordance with themolding shrinkage generally to approximately 75% of the determinedshrinkage dimension. For instance, if mold shrinkage is determined to be0.203 mm (0.008 in), it may be desired to size the undercut to be 0.152mm (0.006 in) from a diameter of the protruding portion of thevalve-gate pin. However, in embodiments such that a retention featurecomprises threaded features, it may be desired to size the depth of thethreaded features to approximately 100% of the determined shrinkagedimension. For instance, if mold shrinkage is determined to be 0.203 mm(0.008 in), it may be desired for depth thread to be 0.203 mm (0.008 in)from a diameter of a protruding portion of a valve-gate pin.

The inventive concept surrounding an injection molding apparatus havinga valve-gate pin may be used in injection molding applications as wellas known to be applicable by those skilled in the art. Furthermore, itwill be appreciated that the inventive concept as disclosed may be usedindividually in applications, as a plurality of units controlledindependently within a system, or a plurality of units controlled inconcert within a system. Such control may be performed in an automotivemanner such as disclosed by U.S. Pat. No. 5,316,707 to Stanciu et al.,herein incorporated by reference in its entirety. A system in which aplurality of valve-gate pins is used may comprise an injection moldhaving a cavity, an injection mold having a plurality of cavities, or aplurality of injection molds. It will be further appreciated that thefeatures of a valve-gate pin as discussed herein, such as retentionfeatures, and a pathway, may be used independently in concert whileremaining in-line with the inventive concepts as discussed herein. Inembodiments comprising a plurality of valve-gate pins operating in asystem, it will be appreciated that certain valve-gate pins may be usedfor the purposes of part retention and part extraction, while othervalve-gate pins are used to control the flow of material into aninjection mold for an injection molding process.

BRIEF DESCRIPTION OF FIGURES

FIG. 1A—A cross-sectional view of an embodiment of an injection moldingapparatus

FIG. 1B—A cross-sectional detail view of an embodiment of an injectionmolding apparatus

FIG. 2—A perspective view of an embodiment of a valve-gate pin

FIG. 3A—A cross-sectional detail view of an embodiment of an injectionmolding apparatus with a valve-gate pin in an open position

FIG. 3B—A cross-sectional detail view of an embodiment of an injectionmolding apparatus with a valve-gate pin in a closed position

FIG. 4—A cross-sectional view of an embodiment of an injection moldingapparatus with a first-side of an injection mold separated from a secondside of an injection mold

FIG. 5—A cross-sectional view of an embodiment of an injection moldingapparatus with a first-side of an injection mold separated from a secondside of an injection mold

FIG. 6A—A detailed view of an embodiment of a valve-gate pin showing anembodiment of a retention feature

FIG. 6B—A detailed view of an embodiment of a valve-gate pin showing anembodiment of a retention feature

FIG. 6C—A detailed view of an embodiment of a valve-gate pin showing anembodiment of a retention feature

FIG. 6D—A detailed view of an embodiment of a valve-gate pin showing anembodiment of a retention feature

FIG. 7—A cross-sectional view of an embodiment of an injection moldingapparatus with a first-side of an injection mold separated from a secondside of an injection mold

FIG. 8—A cross-sectional view of an embodiment of an injection moldingapparatus

FIG. 9—An embodiment of an injection molding method

FIG. 10—An embodiment of an injection molding method

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

Certain embodiments of the present invention, shown in FIG. 1A and FIG.1B, surrounds an injection molding apparatus 1000 comprising avalve-gate pin 1005 installed on a first side 1010 of an injection mold1020. The valve-gate pin 1005, having a shaft 1025, further comprises afirst end 1030 for protruding into a cavity 1040 defined by a first side1010 and a second side 1050 of the injection mold, with the second sidehaving a vent mechanism 1052. The first end 1030 of the valve-gate pincomprises a retention feature 1060. The retention feature 1060 comprisesa first dimension 1070 and a second dimension 1080. The first dimension,proximate to the first end 1030 of the valve-gate pin, is larger thanthe second dimension 1080. Due to the retention feature 1060, when apart 1090 forms in the injection mold 1020, a connection is formedbetween the first end 1030 of the valve-gate pin and the part 1090.Although a retention feature 1060 is typically consistent with the firstend 1030 of the valve-gate pin, it will be appreciated that a retentionfeature 1060 may be offset from the first end 1030 of the valve-gatepin. The valve-gate pin 1005 traverses through a material deliverychamber 1095, through which material passes for the injection into thecavity 1040 of the injection mold. The valve-gate pin 1005 protrudesinto the cavity 1040 through an aperture 1055 extending between thematerial delivery chamber 1095 and the cavity 1040.

A valve-gate pin 1005 as shown in FIG. 1A and FIG. 1B, and disclosedherein, may comprise a material composition of metal, compositematerials such as nano-particle enhanced composites, plastics or othermaterials appreciated by those skilled in the art.

Certain embodiments of a valve-gate pin 1005, for example shown in FIG.2, comprise a first end 1030 with a retention feature 1060. In suchembodiments, the valve-gate pin 1005 comprises a round profile having aplurality of diameters. The retention feature comprises a first diameter1100 consistent with the first end 1030 of the valve-gate pin and asecond diameter 1110 offset from the first end 1030. In suchembodiments, the second diameter 1110 is equal to the minor diameter1130 of an annular recess 1140. In such embodiments, the second diameter1110 of the valve-gate pin 1005 is equal with the major diameter 1150 ofthe annular recess. It will be appreciated, that in other embodiments,the minor diameter 1130 of the annular recess may not equal the seconddiameter 1110 of the valve-gate pin. Furthermore, in other embodiments,the major diameter 1150 of the annular recess may not equal the firstdiameter 1100 of the valve-gate pin. Alternatively, it will be furtherappreciated that a retention feature 1060 may comprise a featureproviding differing form from the first diameter 1100 or the seconddiameter 1110 of the valve-gate pin 1005. Certain embodiments of avalve-gate pin may comprise a form which protrudes from the valve-gatepin.

In embodiments of the present invention, a valve-gate pin 1005, forexample shown in FIG. 3A, is longitudinally positionable to allow theextension and retraction of the valve-gate pin through an aperture 1055and in relation to a cavity 1040 of an injection mold 1020. It will beappreciated that when a valve-gate pin 1005 is in an open position, asecond dimension 1080 of a valve gate pin is configured to interface anaperture 1055 such that material for injecting into a cavity 1040 canbypass the valve-gate pin 1005 into the cavity 1040. In otherembodiments of the present invention, for example shown in FIG. 3B, itwill be appreciated that when a valve-gate pin 1005 is in a closedposition, a first dimension 1070 is configured to be offset from anaperture 1055 such that material for injecting into a cavity 1040 cannotbypass the valve-gate pin 1005 into the cavity 1040.

Certain embodiments of an injection molding apparatus 1000, shown inFIG. 4, are used in conjunction with an injection mold 1020 comprising afirst side 1010 and a second side 1050. The connection of a part 1090 toa valve-gate pin 1005 is accomplished by accounting for materialproperties such as thermal expansion characteristics, stress/strainconsiderations and elasticity of the selected material or compositionused for manufacturing the part 1090. After forming, the part 1090solidifies and contracts in volume causing the part 1090 to be affixedto a retention feature 1060 of the valve-gate pin. The connectionbetween the part 1090 and valve-gate pin 1005 has a retention forcedefined by the force required, directed axially away from the valve-gatepin 1005, to break the connection between the part 1090 and thevalve-gate pin 1005. This retention may be equal to or greater than theforce needed to remove the molded part from the second side 1050 of theinjection mold. When the first side 1010 is separated from the secondside 1050, the retention force of the attachment between the part 1090and the valve-gate pin 1005 pin extracts the part 1090 from the secondside 1050 of the injection mold. If the retention force between the part1090 and the valve-gate pin 1005 is equal to the retention forcesbetween the part 1090 and the second side 1050 of the injection mold,the part releases from the second side 1050 and the first side 1010 ofthe injection mold simultaneously. If the retention between the part1090 and the valve-gate pin 1005 exceeds the retention forces betweenthe part 1090 and the second side 1050 of the injection mold, the part1090 will be pulled away from the second side 1050 and remain in contactwith the valve-gate pin. In certain embodiments, it may be required fora machine operator to manually extract, or a mechanical device to beused to extract, the part 1090 from the first side 1010 of the injectionmold 1020 by applying enough force to break the connection between thepart 1090 and the valve-gate pin 1005.

Certain embodiments of an injection molding apparatus 1000, shown inFIG. 5, comprise a valve-gate pin 1005 configured to retract and extend.It will be appreciated to those skilled in the art that such retractionand extension actions may be performed by linear actuating mechanisms1065 such as, but not limited to, electro-mechanical actuators,mechanical actuators, hydraulic actuators, pneumatic actuators,piezoelectric actuators or other mechanisms known to those skilled inthe art. Typically such actuating mechanisms interface with a second end1035 of the valve-gate pin, but it will be appreciated that theconnection between a valve-gate pin 1005 and an actuation mechanism maycomprise alternate configurations as appreciated by those skilled in theart. In such embodiments, if the part 1090 is still connected to thevalve-gate pin 1005 after the injection mold 1020 has been opened, thevalve-gate pin 1005 may be retracted. The retraction of the valve-gatepin 1005 pulls the valve-gate pin 1005 from the part 1090 with enoughforce to exceed the retention force between the part 1090 and thevalve-gate pin 1005. The retraction distance of the valve-gate pin 1005may be of distance less than, equal to, or greater than the distancewhich the valve-gate pin 1005 protrudes into the cavity 1040 of theinjection mold 1020. Once the part 1090 has been molded and released,the valve-gate pin 1005 may be extended into the cavity 1040 of theinjection mold, and the first side 1010 of the injection mold mated withthe second side 1050 of the injection mold prior to manufacturinganother part 1090.

Certain embodiments of an injection molding apparatus 1000, as shown inFIG. 6A-FIG. 6D, comprising a valve-gate pin 1005 further comprise aretention feature 1060. In such embodiments, the retention feature 1060may comprise at least one alternate form configured to provide retentionof a part 1090. Such embodiments may comprise an annular recess having asemi-circular undercut (FIG. 6A), a rectangular undercut (FIG. 6B), athreaded feature 1200 (FIG. 6C), or a projecting feature 1230 (FIG. 6D).It will be appreciated that a retention feature may comprise any formthat provides a retention force between a retention feature 1060 and apart 1090.

In certain embodiments of an injection molding apparatus 1000, shown inFIG. 7, a valve-gate pin 1005 comprises a retention feature 1060 havinga threaded feature 1200. In such embodiments, the retention feature 1060protrudes into the cavity 1040 of the injection mold 1020. When a part1090 is manufactured, the part 1090 cools and creates an attachmentbetween the part 1090 and the retention feature 1060 of the valve-gatepin. In such embodiments, it may be desired to actuate the valve-gatepin 1005 rotatively to release the part from the retention feature 1060using an actuating mechanism 1065. Such actuation may be performed usingrotative actuating mechanism 1065 independently or in conjunction with alinear actuating mechanism 1065 to retract the valve-gate pin 1005 fromthe cavity 1040 of the injection mold. Rotative actuating mechanisms1065 include technologies such as but not limited to servo motors,stepper motors, hydraulic actuators, and pneumatic actuators. Typically,such actuating mechanisms interface with a second end 1035 of thevalve-gate pin, but it will be appreciated that the connection between avalve-gate pin 1005 and an actuation mechanism may comprise alternateconfigurations as appreciated by those skilled in the art. When the part1090 is released from the retention feature 1060 in such embodiments,the part 1090 exhibits a negative threaded feature 1210 as a negativeform of the threaded feature 1200 of the retention feature 1060.

Certain embodiments of an injection molding apparatus 1000, shown inFIG. 8, comprise a valve-gate pin 1005 having a pathway 1250longitudinally in the valve-gate pin 1005 such that such a pathway 1250is exposed to the cavity 1040 of an injection mold 1020. Such a pathway1250 and typically substantially consistent with a central axis 1260 ofthe valve-gate pin 1005. Such a pathway 1250 provides capability forprocesses including gas-assist injection molding, and gas assisted partejection.

Certain embodiments of an injection molding process 1300, shown in FIG.9, using injection valve-gate pins comprises: Clamping 1305 a first sideof an injection mold to a second side of an injection mold creating acavity between the first side of the injection mold and the second sideof the injection mold, a first positioning step 1310 to position avalve-gate pin to an open position, injecting 1320 material into thecavity between the first side of the injection mold and the second sideof the injection mold, dwelling 1330, maintaining the materialsubstantially motionless under pressure, to ensure all voids of thecavity between the first side of the injection mold and the second sideof the injection mold are filled, a second positioning step 1335 toposition the valve-gate pin to a closed position, cooling 1340 to allowthe part to properly cure and cool thereby creating a connection betweenthe part and the retention feature of the valve-gate pin, separating1350 the first side of the injection mold from the second side of theinjection mold, and a third positioning step 1360 to retract thevalve-gate pin away from the part thereby breaking the connectionbetween the retention feature of the valve-gate pin and the part torelease the part from the first side of the injection mold. Otherembodiments surrounding an injection molding process 1300 comprise: aclamping 1305, a first positioning step 1310, an injecting step 1320,dwelling 1330, a second positioning step 1335, a cooling step 1340, anda separating step 1350. In such embodiments eliminating a thirdpositioning step 1360, a part may be removed from a first side of aninjection mold manually, mechanically, through the use of robotics orthrough the use of automated systems. In certain embodiments, breakingthe connection between the retention feature of the valve-gate pin andthe part may not release the part from the first side of the injectionmold. In such embodiments, it may be desired to add fourth positioningstep 1310 to position the valve-gate pin to force the part away from thefirst side of the injection mold. In certain embodiments of an injectionmolding apparatus which comprise a pathway in a valve-gate pin, as shownin FIG. 10, an additional step of pushing 1380 a fluid through thepathway may be desired. In such embodiments comprising a pushing step1380, it will be appreciated that the pushing step 1380 may occuranywhere throughout the process dependent upon the intended purpose ofthe pushing step 1380. For instance, a pushing step may follow theinjecting step for the introduction of a gas for gas-assist injectionmolding. However, a pushing step may occur following the dwelling step1330 for the purposes of introducing a fluid—including a gas, liquid,powder or flowable solid—to encapsulate the fluid within the part.Furthermore, the pushing step may occur following the retracting 1360step to provide gas-assisted ejection of a part from the injection mold.It will be appreciated by those skilled in the art that steps including,but not limited to, positioning 1310 the valve-gate pin and, retracting1360 the valve-gate pin may occur at alternate stages of the processwhile remaining consistent with the inventive nature of the presentinvention.

In the foregoing specification, specific embodiments have beendisclosed. However, one of ordinary skill in the art appreciates thatvarious modifications and changes can be made without departing from thescope of the invention as set forth in the claims below. Accordingly,the specification and figures are to be regarded in an illustrativerather than a restrictive sense, and all such modifications are intendedto be included within the scope of present teachings. It is understoodthat the invention may be embodied in other specific forms withoutdeparting from the spirit or central characteristics thereof. Thepresent examples and embodiments, therefore, are to be considered in allrespects as illustrative and not restrictive, and the invention is notto be limited to the details given herein. The terms “first,” “second,”“proximal,” “distal,” etc., as used herein, are intended forillustrative purposes only and do not limit the embodiments in any way.Additionally, the term “plurality,” as used herein, indicates any numbergreater than one, either disjunctively or conjunctively, as necessary,up to an infinite number. The benefits, advantages, solutions toproblems, and any element(s) that may cause any benefit, advantage, orsolution to occur or become more pronounced are not to be construed as acritical, required, or essential features or elements of any or all theclaims.

While various embodiments of the present invention have been describedin detail, it is apparent that modifications and alterations of thoseembodiments will occur to those skilled in the art. However, it is to beexpressly understood that such modifications and alterations are withinthe scope and spirit of the present invention. Further, the invention(s)disclosed herein are capable of other embodiments and of being practicedor of being carried out in various ways. Various embodiments of thepresent invention(s) have been described in detail, it is apparent thatmodifications and alterations of those embodiments will occur to thoseskilled in the art. In addition, it is to be understood that thephraseology and terminology used herein is for the purposes ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “adding” and variations thereof herein aremeant to encompass the items listed thereafter and equivalents thereof,as well as, additional items.

What is claimed is:
 1. An injection molding apparatus for the extractionof a part comprising: a first side of an injection mold and a secondside of an injection mold having a cavity therebetween; said first sideof said injection mold further comprising a material delivery chamberand an aperture extending from said material delivery chamber to saidcavity; a first valve-gate pin having a first end, said first end ofsaid first valve-gate pin disposed through said aperture with said firstend protruding into said cavity; said valve-gate pin having a retentionfeature proximate to said first end of said first valve-gate pin; saidretention feature comprising a first dimension proximate to said firstend of said first valve-gate pin, and a second dimension offset fromsaid first dimension toward a second end of said first valve-gate pin;said first dimension is greater than said second dimension; and saidfirst valve-gate pin having connection to an actuating mechanism whereinsaid actuating said first valve-gate pin is positionable through saidaperture.
 2. The injection molding apparatus of claim 1, wherein saidretention feature comprises an annular recess.
 3. The injection moldingapparatus of claim 1, wherein said retention feature comprises athreaded feature.
 4. The injection molding apparatus of claim 1, whereinsaid retention feature comprises a projecting feature.
 5. The injectionmolding apparatus of claim 1, wherein said first valve-gate pin furthercomprises a pathway.
 6. The injection molding apparatus of claim 5,wherein said pathway is consistent with a central axis of said firstvalve-gate pin.
 7. The injection molding apparatus of claim 1, whereinsaid valve-gate pin is constructed of a material selected from the listconsisting of: metals, polymeric, composite, nano-particle enhancedcomposite.
 8. The injection molding apparatus of claim 1, wherein saidinjection molding apparatus further comprises a second valve-gate pin.9. The injection molding apparatus of claim 1, wherein said actuatingmechanism is programmably controlled.
 10. A method for the injectionmolding of a part comprising: clamping a first side of an injection moldto a second side of an injection mold creating a cavity therebetween; afirst positioning step to position a valve-gate pin to an open position;injecting a first material into said cavity; a maintaining step to holdsaid injected material under pressure within said injection mold for apredetermined period of time; a second positioning step to position avalve-gate pin to a closed position; and opening said injection mold, toseparate said first side of said injection mold from said second side ofsaid injection mold;
 11. The method of claim 10 further comprising afourth positioning step following said third positioning step toposition the valve-gate pin to force the part away from the first sideof the injection mold.
 12. The method of claim 10 further comprisingpushing a second material through a pathway in said valve-pin.
 13. Themethod of claim 11, wherein said second material comprises a gaseousmaterial.
 14. The method of claim 10, wherein said first positioningstep occurs prior to said clamping step.
 15. The method of claim 10further comprising a third positioning step to retract said valve-gatepin thereby breaking a connection between said valve-gate pin and saidpart.